The present invention relates to portable sign stands, and more particularly, to a leg release mechanism for quickly and easily locking a sign stand leg in a retracted or protracted position.
There are many uses for signage products today, particularly for traffic control at road construction sites and other work areas along the nation""s highways. Many of these signage products utilize portable sign stands or sign holders for temporarily locating and displaying signs of various sizes and shapes. Rigid signs such as aluminum or plywood have typically been used in such applications. However, there has been a recent trend, particularly with portable traffic control signage, towards the use of flexible, roll-up signs, which have been well-received due to their lightweight and compact nature. It is anticipated that this trend will continue due to benefits gained by the compactness, portability and storability of flexible sign systems, as well as the durability of their design and the minimal maintenance required for their upkeep.
In general, various portable sign stands have been developed which utilize an upright that is attached to a base assembly having a leg assembly including a number of legs that pivotally and telescopically extend to support the sign. In addition, the legs are generally positionable between a retracted position wherein the legs are positioned closely parallel to the upright for convenient storage and a protracted position wherein the legs extend outwardly from the upright for securely supporting the sign. A release mechanism is incorporated into the base assembly for releasably securing the legs in the retracted or protracted position. The base assembly often includes a resilient spring member between the leg assembly and the upright to control deflection of the sign whenever a force is applied thereto, such as a gust of wind impinging upon the sign panel.
The flexible roll-up sign has a pair of brace members attached to the corners of a flexible sign panel which in a deployed or use position form a cross configuration. Various fasteners can be used for this purpose including twist lock fasteners, hook and loop type fasteners, snaps, plastic pockets or stretchable rubber or elastic straps. Fasteners of the latter type are marketed and sold by Marketing Displays International, Inc. of Farmington Hills, Mich. under the trademark DuraLatch(trademark). The flexible roll-up sign is releasably secured to the sign stand by a locking mechanism such as a cam lock or lock pin assembly.
Preferred embodiments of the type of sign stands described above are disclosed in the following U.S. patents: U.S. Pat. No. 6,056,250 entitled xe2x80x9cImproved Sign Stand For Flexible Traffic Control Signagexe2x80x9d, U.S. Pat. No. 6,032,908 entitled xe2x80x9cSign Stand With Cam Release Assemblyxe2x80x9d and U.S. Pat. No. 5,472,162 entitled xe2x80x9cCap Lock For Sign Stand.xe2x80x9d The above-referenced applications are commonly owned by the assignee of the present invention and the disclosures are expressly incorporated by reference herein.
Signage systems of the type described above have several moving parts that must operate easily and repeatedly in adverse conditions with little or no maintenance. These signage systems are commonly set up along busy roads and highways such that continuous efforts are made to improve the ease of use and durability of these systems. In this regard, there is a need to provide a release mechanism for the leg assembly, and more particularly to provide a simpler, more cost-effective release mechanism for the leg assembly which is simple to assemble, quick and easy to operate and requires no significant maintenance and is substantially wear-resistant.
It is a principle object of the present invention to provide a portable sign stand having an improved leg release mechanism for releasably positioning the legs of the stand between a retracted position and multiple protracted positions.
It is another object of the present invention to provide a method of constructing an improved leg release mechanism, which is low in cost and simple to manufacture and assemble.
It is a further object of the present invention to provide an improved xe2x80x9cfoot-operatedxe2x80x9d leg release mechanism for releasably locking the leg assembly in the retracted or protracted positions.
Accordingly, the present invention is directed to a portable sign stand comprising a base assembly having a leg pivotally connected to a base plate and a release mechanism for selectively permitting pivoting of the leg relative to the base plate. The release mechanism includes a lock-pin slidably disposed through a cavity of the leg between a first and second position. In the first position the lock-pin extends into an aperture of the base plate and in the second position the lock-pin is withdrawn from the aperture. A biasing member is disposed within the cavity and in direct connection with the lock-pin for biasing the lock-pin in the first position. When the lock-pin is in the first position pivoting of the leg relative to the base plate is disabled. When the lock-pin is in the second position pivoting of the leg relative to the base plate is enabled.
Further areas of applicability of the present invention will become apparent from the detailed description provided hereinafter. It should be understood that the detailed description and specific examples, while indicating the preferred embodiment of the invention, are intended for purposes of illustration only and are not intended to limit the scope of the invention.